Frequency band resources are in shortage due to increase in mobile data services, and mobile data services in large quantities may not be achievable through network deployment and service transmissions using only authorized frequency band resources. In view of above, it is optional to deploy transmissions of mobile data services using unauthorized frequency band resources, to enhance utilization ratio of frequency band resources and improve user experience. An unauthorized frequency band that serves as an auxiliary carrier assists an authorized frequency band that serves as a main carrier in achieving transmissions of mobile data services.
The unauthorized frequency band can be shared by various wireless communications systems such as Bluetooth and Wi-Fi, and the various wireless communications systems uses the shared unauthorized frequency band resources through competing for the resources. Hence, it is important and difficult in research how to ensure unlicensed long term evolutions (abbreviated as U-LTEs or LTE-Us) deployed by different service providers to co-exist or how to ensure different wireless communications systems such as LTE-U and Wi-Fi to co-exist.
An LTE system may support frequency division duplexing (FDD) and time division duplexing (TDD) that adopt different frame structures. In the two different frame structures, each radio frame consists of ten subframes each last 1 ms. The FDD system adopts a first frame structure as shown in FIG. 1, and the TDD system adopts a second frame structure as shown in FIG. 2.
It can be found from the LTE frame structure, the data is transmitted in unit of subframe that lasts 1 ms. In the LTE-U, due to factors such as listen before talk (LBT) competitive access, data preparation time in a base station and radio frequency preparation time in a base station, a start time point for transmission of a LTE-U signal starts may be located at any position within one subframe, such that an incomplete subframe, i.e., a physical resource that lasts a period shorter than a length of one normal subframe, is transmitted. If no signal is sent using the incomplete subframe, the resource is of course to be taken by other nodes in situation of intense resource competition.
To ensure fair competition between LTE-U and Wi-Fi, the LTE-U may be designed with each transmission lasting 10 ms, and each transmission is better not longer than 40 ms. In the case that the LTE-U is designed with each transmission lasting about 10 ms and any incomplete subframe is not used for transmission, transmission efficiency of the LTE-U is greatly decreased. In the case that an incomplete subframe is transmitted on a resource that is not available for transmitting a complete subframe and the incomplete subframe is used in data transmission, the data transmission efficiency can be enhanced and resource is not wasted. However, there is no technical solution for performing data transmission using incomplete subframe in an LTE unauthorized frequency band.
In sum, no solution is given in related art to achieve data transmission using incomplete subframe in the unauthorized frequency band.